(CBS) PORT DEPOSIT, Md. - A family friend of Kami Ring, a 10-year-old Maryland girl found dead in a field in Port Deposit Monday night, has been arrested and charged with raping and murdering the young girl, CBS Baltimore reports.

Maryland State Police say they arrested 29-year-old Richard Madden Thursday evening without incident. He is charged with first and second-degree murder, first-degree assault and first-degree rape, according to a news release from the police.

At the time of his arrest, Madden was reportedly already being held at the Cecil County Detention Center in Elkton for violating his probation stemming from drug charges.

Kami, who was from Charleston, Md., was reported missing from a home in Port Deposit Monday morning. Investigators were told that the 10-year-old was last seen Sunday night at the home and it had been assumed she had gone to bed. Police say a window screen in the bedroom where the girl had been staying was pushed out.

The home in Port Deposit is owned by family friends, who were like grandparents to Kami, according to the station. She was staying with them at the time she went missing.

Police say they found Kami's body Monday evening near a shed in a field about 60 yards in front of the home.

Richard Madden, who police arrested, is reportedly the homeowners' son. Maryland State Police say Madden was one of three people living in that home.

According to CBS Baltimore, newly released autopsy results show Kami died form blunt force trauma and asphyxiation.

A motive had not been released in the case and the Maryland State Police's homicide unit says the investigation is ongoing.